In order to construct the of medical service audit model of public hospitals in the context of big data, it takes the practical exploration of the First Affiliated Hospital of the University of Science and Technology of China as an example, proposes the audit model design ideas, and sorts out the rules and modeling steps related to medical service price, drug purchase and sale inventory, and consumables purchase and sale inventory, respectively. Using the above model to analyze and process business data, potential risks and business suspicions are discovered in time, improving the accuracy, timeliness and risk prediction ability of internal audit, and promoting fine management and high-quality development of the hospital.